Grass from your Favorite Stadium

Grass grows back really quickly when you cut a section out.  I was driving past a turf farm watching them cut up sections of grass when I had a thought.  Why can't baseball or football stadiums do the same thing.  They could take a section of the field that isn't part of the field of play and cut out grass sections (that would replace themselves) and sell the grass in little squares to fanatics?

Question:

What field square would you buy?